Tuna Tetrazzini - Tuna and Spaghetti Casserole

Tuna and spaghetti team up with mushrooms and Parmesan cheese in this tuna tetrazzini recipe. It's a whole meal in one pot and can be prepared a day in advance, making it a convenient and tasty dish for a busy day.

Serve the tuna casserole with crusty bread or biscuits and a simple tossed salad if you'd like.

How to Make It

Heat oven to 350 F.

Grease a 2 1/2- to 3-quart baking dish.

Cook the spaghetti following the package directions. Drain and set aside.

In a large saucepan over medium-low heat, melt 4 tablespoons of the butter. Add the mushrooms and saute, stirring, until mushrooms are browned and tender. Add the green onions and continue cooking for 1 minute. Stir in the flour until well blended. Gradually stir in the milk. Continue cooking, stirring constantly, until thickened. Add salt, to taste, and pepper. Stir in the flaked tuna and peas.

Combine the tuna sauce mixture with the drained spaghetti until well blended. Turn the mixture into the prepared casserole. Sprinkle Parmesan cheese over the casserole.

Bake in the preheated oven for 25 to 30 minutes, until lightly browned and bubbly.

Serves 6.

Make Ahead Tip: Combine the tuna, spaghetti, vegetables, sauce up to a day in advance. Spoon into the baking dish; cover and refrigerate until about 30 minutes before you plan to bake it. Top with the Parmesan cheese and buttered bread crumbs and bake as directed, until the topping is browned and the filling is bubbling around the edges.